Sweet's syndrome and erythema nodosum: the simultaneous occurrence of 2 reactive dermatoses

[Erythema nodosum]

Erythema nodosum (EN) is the most frequently occurring form of acute panniculitis. It is characterized by painful red to livid raised nodules or bumps that typically occur symmetrically in the shin area. The cause of EN is often a reaction of the immune system to various triggers including infections, inflammatory diseases or medications. In approximately half of the cases no trigger can be identified. After treatment of the underlying pathology EN is typically self-limiting.

Sweet or Not? Azathioprine-Induced Sweet Syndrome Mimicking Erythema Nodosum in a Patient With Inflammatory Bowel Disease

This case report highlights the clinical challenge and need to distinguish Sweet syndrome and erythema nodosum (EN) in a 50-year-old woman with newly initiated azathioprine for inflammatory bowel disease. While she initially presented with clinical features concerning for drug-induced Sweet syndrome, a subsequent histopathological examination confirmed early-stage EN. Both Sweet syndrome and EN share common triggers and therapeutic responses, but have distinctive clinical characteristics. Subtle histologic differences also exist in lesion distribution and depth of infiltration. This case underscores the need for accurate differentiation in patients with inflammatory bowel disease to initiate appropriate management and avoid potential complications.

Sequential occurrence of recurrent Sweet syndrome and erythema nodosum without an underlying secondary cause: a case report

BACKGROUND

Sweet syndrome is a rare cause of acute fever and painful erythematous skin plaques. Erythema nodosum is acute or chronic tender erythematous skin nodules of bilateral shins. The concurrent presence of both dermatoses is rare but reported in the literature. There are no reported cases of recurrent and sequential Sweet syndrome and erythema nodosum without an underlying secondary cause.

CASE PRESENTATION

We report the case of a 64-year-old Asian woman, who had possible Sweet syndrome 12 years ago and biopsy-proven erythema nodosum 5 years ago, presenting with an acute episode of Sweet syndrome. Extensive investigations did not reveal any underlying secondary cause.

CONCLUSIONS

Recurrent Sweet syndrome and sequential presence with erythema nodosum raises suspicion if Sweet syndrome and erythema nodosum are different presentations of one disease, which warrants further study. This case proves that recurrent Sweet syndrome and erythema nodosum can occur in healthy individuals without an underlying malignancy or secondary cause.

Systematic Review: Sweet Syndrome Associated with Inflammatory Bowel Disease

BACKGROUND AND AIMS

Sweet syndrome [SS] is a dermatological condition associated with both inflammatory bowel disease [IBD] and azathioprine use. We performed a systematic review to better delineate clinical characteristics and outcomes of SS in IBD patients.

METHODS

Peer-reviewed, full-text journal publications from inception to April 2020 in English language and adult subjects with IBD were included. Skin biopsy was required as SS gold-standard diagnosis. Azathioprine-associated SS required recent azathioprine introduction or recurrence of SS after azathioprine re-challenge.

RESULTS

We included 89 publications with 95 patients [mean age of SS diagnosis: 44 years; 59% female; 20 with azathioprine-associated SS and 75 without]. SS was diagnosed prior to IBD in 5.3%, at time of IBD diagnosis in 29.5% and after diagnosis in 64.2%. In total, 91% of patients with SS had known colonic involvement and the majority [76%] had active IBD at diagnosis; 22% had additional extra-intestinal manifestations. Successful therapies for SS included corticosteroids [90.5%], anti-tumour necrosis factor [TNF]-α inhibitor therapy [14.8%] and azathioprine [11.6%]. Azathioprine-associated SS was distinct, with 85% male patients, mean age of SS diagnosis of 50 years and a lower likelihood to be prescribed corticosteroids for treatment [75% vs 94.7% of non-azathioprine-associated SS, p = 0.008]. All patients with azathioprine-associated SS improved with medication cessation and developed recurrence after re-challenge.

CONCLUSIONS

SS may precede or occur with IBD diagnosis in almost one-third of cases. Azathioprine and IBD-associated SS present and behave distinctly, especially with regard to gender, age at diagnosis and recurrence risk. Corticosteroids and TNF-α inhibitors have demonstrated efficacy in treating SS in IBD.

Insights Into the Pathogenesis of Sweet's Syndrome

Sweet's syndrome, also known as Acute Febrile Neutrophilic Dermatosis, is a rare inflammatory condition. It is considered to be the prototype disease of neutrophilic dermatoses, and presents with acute onset dermal neutrophilic lesions, leukocytosis, and pyrexia. Several variants have been described both clinically and histopathologically. Classifications include classic Sweet's syndrome, malignancy associated, and drug induced. The cellular and molecular mechanisms involved in Sweet's syndrome have been difficult to elucidate due to the large variety of conditions leading to a common clinical presentation. The exact pathogenesis of Sweet's syndrome is unclear; however, new discoveries have shed light on the role of inflammatory signaling, disease induction, and relationship with malignancy. These findings include an improved understanding of inflammasome activation, malignant transformation into dermal infiltrating neutrophils, and genetic contributions. Continued investigations into effective treatments and targeted therapy will benefit patients and improve our molecular understanding of inflammatory diseases, including Sweet's syndrome.

Acute myeloid leukemia presenting as erythema nodosum: A case report

RATIONALE

Erythema nodosum (EN), a type of septal panniculitis, could be a rare nonspecific cutaneous presentation of acute myeloid leukemia (AML).

PATIENT CONCERNS

A 58-year-old Chinese female was admitted for a 4-week history of painful cutaneous lesions, accompanied by a sternal pain and fever. The lesions once resolved spontaneously but then recurred. Physical examination revealed warm, tender, indurated, rounded, erythematous to violaceous nodules in bilateral lower extremities, ranging in diameter from 1 to 6 cm. Blood marrow examination was compatible with AML-M2.

DIAGNOSES

AML-M2 presenting as EN.

INTERVENTIONS

Daunorubicin and cytarabine were used in induction chemotherapy. The patient achieved complete remission and her skin lesions disappeared simultaneously. Six courses of consolidation chemotherapy were conducted in the following 6 months.

OUTCOMES

The patient died due to AML relapse.

LESSONS

The case strengthens the awareness of cutaneous involvement of AML and raises oncological vigilance in patients with EN.

Neutrophilic dermatosis of dorsal hands

Sweet's syndrome is characterized by erythematous tender nodules and plaques over face and extremities. Fever, leukocytosis with neutrophilia, and a neutrophilic infiltrate in the dermis are characteristic features. Neutrophilic dermatosis of dorsal hands is a rare localized variant of Sweet's syndrome occurring predominantly over dorsa of hands. Various degrees of vascular damage may be observed on histopathology of these lesions. Both Sweet's syndrome and its dorsal hand variant have been reported in association with malignancies, inflammatory bowel diseases, and drugs. We report a patient with neutrophilic dermatoses of dorsal hands associated with erythema nodosum. He showed an excellent response to corticosteroids and dapsone.

Neutrophilic dermatoses in a patient with collagenous colitis

We report the case of a 75-year old woman with collagenous colitis who presented with erythematous and edematous plaques on the periorbital and eyelid regions, accompanied by oral ulcers. Histopathology showed a dermal neutrophilic infiltrate plus mild septal and lobular panniculitis with lymphocytes, neutrophils and eosinophils. Five years earlier she had presented a flare of papules and vesicles on the trunk, together with oral ulcers; a skin biopsy revealed a neutrophilic dermal infiltrate and Sweet’s syndrome was diagnosed. Both the neutrophilic panniculitis and the Sweet’s syndrome were accompanied by fever, malaise and diarrhea. Cutaneous and intestinal symptoms disappeared with corticoid therapy. The two types of neutrophilic dermatoses that appeared in periods of colitis activity suggest that intestinal and cutaneous manifestations may be related.

Panniculitis as the presenting sign of a myelodysplastic syndrome in an adolescent boy

Panniculitis is an uncommon condition in childhood and may prove difficult to diagnose both clinically and histologically. The clinical spectrum is similar to that in adults and has been associated with many primary diseases. Noninfectious causes are less common in children than in adults. The pathogenesis remains uncertain in a significant number of children. In some it may be a malignant, unremitting disease which can be fatal. We present a boy aged 13 years with panniculitis of the right foot as presenting sign for the ultimate diagnosis myelodysplasia-acute myeloid leukemia. To our knowledge this is the first report on a young boy.

Sweet's syndrome--a comprehensive review of an acute febrile neutrophilic dermatosis

Sweet's syndrome (the eponym for acute febrile neutrophilic dermatosis) is characterized by a constellation of clinical symptoms, physical features, and pathologic findings which include fever, neutrophilia, tender erythematous skin lesions (papules, nodules, and plaques), and a diffuse infiltrate consisting predominantly of mature neutrophils that are typically located in the upper dermis. Several hundreds cases of Sweet's syndrome have been published. Sweet's syndrome presents in three clinical settings: classical (or idiopathic), malignancy-associated, and drug-induced. Classical Sweet's syndrome (CSS) usually presents in women between the age of 30 to 50 years, it is often preceded by an upper respiratory tract infection and may be associated with inflammatory bowel disease and pregnancy. Approximately one-third of patients with CSS experience recurrence of the dermatosis. The malignancy-associated Sweet's syndrome (MASS) can occur as a paraneoplastic syndrome in patients with an established cancer or individuals whose Sweet's syndrome-related hematologic dyscrasia or solid tumor was previously undiscovered; MASS is most commonly related to acute myelogenous leukemia. The dermatosis can precede, follow, or appear concurrent with the diagnosis of the patient's cancer. Hence, MASS can be the cutaneous harbinger of either an undiagnosed visceral malignancy in a previously cancer-free individual or an unsuspected cancer recurrence in an oncology patient. Drug-induced Sweet's syndrome (DISS) most commonly occurs in patients who have been treated with granulocyte-colony stimulating factor, however, other medications may also be associated with DISS. The pathogenesis of Sweet's syndrome may be multifactorial and still remains to be definitively established. Clinical and laboratory evidence suggests that cytokines have an etiologic role. Systemic corticosteroids are the therapeutic gold standard for Sweet's syndrome. After initiation of treatment with systemic corticosteroids, there is a prompt response consisting of dramatic improvement of both the dermatosis-related symptoms and skin lesions. Topical application of high potency corticosteroids or intralesional corticosteroids may be efficacious for treating localized lesions. Other first-line oral systemic agents are potassium iodide and colchicine. Second-line oral systemic agents include indomethacin, clofazimine, cyclosporine, and dapsone. The symptoms and lesions of Sweet's syndrome may resolved spontaneously, without any therapeutic intervention; however, recurrence may follow either spontaneous remission or therapy-induced clinical resolution.

Erythema Nodosum

Erythema nodosum is the most frequent clinicopathologic variant of panniculitis. The process is a cutaneous reaction that may be associated with a wide variety of disorders, including infections, sarcoidosis, rheumatologic diseases, inflammatory bowel diseases, medications, autoimmune disorders, pregnancy, and malignancies. Erythema nodosum typically manifest by the sudden onset of symmetrical, tender, erythematous, warm nodules and raised plaques usually located on the lower limbs. Often the lesions are bilaterally distributed. At first, the nodules show a bright red color, but within a few days they become livid red or purplish and, finally, they exhibit a yellow or greenish appearance, taking on the look of a deep bruise. Ulceration is never seen, and the nodules heal without atrophy or scarring. Histopathologically, erythema nodosum is the stereotypical example of a mostly septal panniculitis with no vasculitis. The septa of subcutaneous fat are always thickened and variously infiltrated by inflammatory cells that extend to the periseptal areas of the fat lobules. The composition of the inflammatory infiltrate in the septa varies with age of the lesion. In early lesions edema, hemorrhage, and neutrophils are responsible for the septal thickening, whereas fibrosis, periseptal granulation tissue, lymphocytes, and multinucleated giant cells are the main findings in late stage lesions of erythema nodosum. A histopathologic hallmark of erythema nodosum is the presence of the so-called Miescher's radial granulomas, which consist of small, well-defined nodular aggregations of small histiocytes arranged radially around a central cleft of variable shape. Treatment of erythema nodosum should be directed to the underlying associated condition, if identified. Usually, nodules of erythema nodosum regress spontaneously within a few weeks, and bed rest is often sufficient treatment. Aspirin, nonsteroidal antiinflammatory drugs, such as oxyphenbutazone, indomethacin or naproxen, and potassium iodide may be helpful drugs to enhance analgesia and resolution. Systemic corticosteroids are rarely indicated in erythema nodosum and before these drugs are administered an underlying infection should be ruled out.

Sweet's syndrome and sarcoidosis

In this review we summarize a number of cases of Sweet's syndrome (SS) associated with sarcoidosis that have been reported in the English literature. In all of the cases, the two disorders were diagnosed simultaneously. Patients with both disorders were younger and had a higher rate of fever than patients with SS alone. In this group of patients, we found a trend toward less skin involvement of the face and trunk, more involvement of the upper limbs, and more atypical skin lesions, particularly papules. The association of the two disorders seems to be more related to a subset of acute sarcoidosis (Lofgren's syndrome). All of the patients in this group had a benign course and self-limiting disease. Thus, SS in association with sarcoidosis could be considered a favorable prognostic factor. Although SS has a high rate of recurrence, no recurrence occurred in this group of patients during follow-up.

Crohn's disease associated with Sweet's syndrome and Sjögren's syndrome treated with infliximab

The association of Crohn's disease (CD) and Sweet's syndrome is rare and the presence of Sjögren's syndrome in Crohn's disease is even rarer, with only three reports found in the literature. We describe two cases of Crohn's disease associated with Sweet's syndrome, one of which is the first case of CD and Sweet's concomitantly associated with Sjögren's syndrome. Both cases responded rapidly to Infliximab therapy with complete resolution of the skin lesions.

Concurrent occurrence of Sweet's syndrome and erythema nodosum: an overlap in the spectrum of reactive dermatoses

Simultaneous occurrence of Sweet's syndrome and erythema nodosum is very rare. We describe a case of a young male with a recent history of streptococcal infection who presented with concurrent Sweet's syndrome and erythema nodosum. Although the exact pathogenesis of these dermatoses is not yet clear, their similarities and simultaneous occurrence suggest a possible common underlying mechanism and may represent a continuum of reactive dermatoses. Evaluation of the role of cytokines in the etiopathogenesis of these conditions will be useful for further assessment and treatment of these conditions. Like the association of acanthosis nigricans and certain cancers and diabetes, Sweet's syndrome and erythema nodosum may be associated with certain malignancies, autoimmune disorders, or inflammatory bowel disease. Early recognition of these skin lesions can guide a search for underlying disorders. Patients with Sweet's syndrome should undergo an age-appropriate work-up for malignancy.

Sweet's syndrome revisited: a review of disease concepts

Sweet's syndrome, also referred to as acute febrile neutrophilic dermatosis, is characterized by a constellation of symptoms and findings: fever, neutrophilia, erythematous and tender skin lesions that typically show an upper dermal infiltrate of mature neutrophils, and prompt improvement of both symptoms and lesions after the initiation of treatment with systemic corticosteroids. Hundreds of patients with this dermatosis have been reported. The manifestations of Sweet's syndrome in these individuals have not only confirmed those originally described by Dr Robert Douglas Sweet in 1964, but have also introduced new features that have expanded the clinical and pathologic concepts of this condition. The history, clinical characteristics, laboratory findings, associated diseases, pathology, and treatment options of Sweet's syndrome are reviewed. The evolving and new concepts of this dermatosis that are discussed include: (i) Sweet's syndrome occurring in the clinical setting of a disease-related malignancy, or medication, or both; (ii) detection of additional sites of extracutaneous Sweet's syndrome manifestations; (iii) discovery of additional Sweet's syndrome-associated diseases; (iv) variability of the composition and/or location of the cutaneous inflammatory infiltrate in Sweet's syndrome lesions; and (v) additional efficacious treatments for Sweet's syndrome.

Sweet's syndrome evolved from recurrent erythema nodosum in a patient with myelodysplastic syndrome

A 63-year-old man had painful nodules on his lower legs. Microscopic examination showed septal and lobular panniculitis composed of lympho-histiocytic infiltrates. Based on the clinical and histopathological findings, the diagnosis of erythema nodosum (EN) was made. Nonsteroidal anti-inflammatory drugs were temporarily effective, but the eruptions had repeated to the present, and 16 months later, myelodysplastic syndrome (MDS) was diagnosed. Then, 6 months later, he developed a high fever and edematous fresh red-colored nodules on his neck, arm and upper trunk. Histopathologically, a diffuse, dense, dermal infiltrate of neutrophils was seen, and Sweet's syndrome (SS) was diagnosed. SS is known to develop in patients with MDS, and EN is one of the dermatoses that occur in conjunction with hematoproliferative disorders. Furthermore, SS evolving from recurrent EN and the simultaneous occurrence of SS and EN have been reported in some patients. In our case, we suggest that some mediators such as cytokines associated with MDS might have first induced EN, and then, as the MDS developed, they were replaced by others that caused SS.